Creates an instance of a video composition output for reading composited video from the specified video tracks, using optional video settings.
- iOS 4.1+
- macOS 10.7+
- Mac Catalyst 13.0+
- tvOS 9.0+
An array of
AVAssetobjects from which the created object should read video frames for compositing.
Each track must be one of the tracks owned by the target asset reader’s asset and must be of media type AVMediaTypeVideo.
A dictionary of video settings to be used for sample output, or
nilif you want to receive decoded samples in a convenient uncompressed format, with properties determined according to the properties of the specified video tracks.
You use keys from
CVPixel, depending on the output format you want.
Initialization will fail if the video settings cannot be used with the specified video tracks.
An instance of
video, using the settings specified by
nil if initialization failed.